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Previous studies from our lab have created a simple procedure for single-cell count of bacteria on a paper chip platform using optical detection from a smartphone. The procedure and steps employed are outlined along with the lessons learned and details of certain steps and how the design was optimized. Smartphone optical detection is easy to use, low cost, and potentially field deployable, which can be useful for early and rapid detection of pathogens. Smartphone imaging of a paper microfluidic chip preloaded with antibody-conjugated particles provides an adaptable platform for detection of different bacterial targets. The paper microfluidic chip was fabricated with a multichannel design. Each channel was preloaded with either a negative control of bovine serum albumin (BSA) conjugated particles, anti-Salmonella Typhimurium-conjugated particles with varying amounts (to cover different ranges of assay), or anti-Escherichia coli-conjugated particles. Samples were introduced to the paper microfluidic chip using pipetting. Antigens of Salmonella Typhimurium traveled through the channel by capillary action confined within the paper fibers surrounded by the hydrophobic barrier. The paper channel was observed to act as a filter for unwanted particles and contaminants found in field samples. Serial dilutions of known concentrations of bacterial targets were also tested using this procedure to construct a standard curve prior to the assays. The antibody-conjugated particles were able to immunoagglutinate which was quantified through evaluation of Mie scatter intensity. This Mie scattering was quantified in images taken with a smartphone at an optimized angle and distance. Mie scatter simulation provided a method of optimizing the experimental setup and could translate easily to other types of target sample matrices. A smartphone application was developed to help the user position the smartphone optimally in relation to the paper microfluidic chip. The application integrated both image capturing capability and a simple image processing algorithm that calculated bacteria concentrations. The detection limit was at a single-cell level with a total assay time ranging from 90 to less than 60 s depending on the target.

Studies on aetiology are typically designed to establish links between determinants and outcomes. We have also included in this group studies that describe iatrogenic or harmful effects of medical interventions.

Studies on prognosis are characterised by observations of different outcomes of a disorder. They are focused on the spectrum of severity, on a certain stage of a disorder, etc. Their results are used in practice to predict future disease events.

In this chapter we discuss some issues about the validity, importance and usefulness of studies on treatment. Here, we work with a broad concept of treatment that is inclusive of primary, secondary and tertiary preventive interventions.

Guidelines can have a strong influence in clinical decision-making and clinical practice. Because of their potential effect on practice behaviour, the information presented in guidelines must be rigorously evaluated.

Boron Neutron Capture Therapy (BNCT) can only be conceived in the framework of a large multidisciplinary team. Clinical papers presented at the Fifth International Symposium on Neutron Capture Therapy for Cancer can roughly be divided into 3 groups, according to the team to which the authors belong, each of which has its particular concerns, reflecting the level of advancement of the project. A number of papers stemmed from authors which were already applying BNCT to patients with intracranial tumors and melanomas,1-8 and these mostly reflected attempts to refine and improve the current treatment methods. An equal number stemmed from authors who intended to start clinical trials shortly,9-18 dealing with beam and treatment room design, quality control and clinical biodistribution of boron compounds, and protocol design. A small number of clinical papers dealt with those lesions, which may become candidates for BNCT, as well as with new boron compounds, preparing the future beyond intracranial tumors and melanomas, and beyond BSH and BPA.3,19,20

The four papers of this section deal with rather different subjects. Nonetheless, I will try to emphasize certain common points in the approaches.

The muscles used in these two studies, the masseter of the rabbit (Saed et al.) and the first lumbrical of the human hand (Thornell et al.) would seem to have very little in common. The first lumbrical has been intimately involved in some of the highest cultural achievements of human beings, since it is the muscle needed to apply pressure by the tip of the index finger against the thumb when holding a pen or paintbrush. However, one cannot be homocentrically dismissive about a muscle merely dedicated to lagomorph nutrition after reading the paper by Saed et al. The control of both these muscles must be closely coordinated not only with the control of several other muscles, but also with sensory information from the skin and joints of the hand in the lumbrical case, and from the buccal cavity and mandibular joints in the masseter case. But the rabbit masseter has an impressive versatility in addition, due to its internal organisation. As Saed et al explain it is divided by partitions into multiple compartments, from superficial to deep, capable of being activated successively, and possibly differentially even within each compartment. Surprisingly, however, this peripheral anatomical order was not reflected in a topographical organisation of the motoneurone cell bodies, which occur in two groups, in the trigeminal motor nucleus, and in cell group k, a separate collection of small fusiform neurones.

Since the last International Coronavirus Meeting a number of very intriguing papers have appeared. These papers have provided insight into what continues to be a very exciting and complex interaction between MHV strains and their natural hosts and include studies of viral tropism, pathogenesis, the role of immune system and genetic factors. MHV infections in mice have been studied mainly as models of viral hepatitis (4,7,9,11,13) and both acute and chronic viral infection of the central nervous system (CNS) (2,5,6,8,15–17,19,20).

The work described here concerns the ontogenetic development of intrafusal muscle fibres and their innervation. The present view, derived from previous work from several laboratories, is that the bag2 fibre of the muscle spindle develops from a primary myotube prenatally, its specialization from extrafusal precursors being associated with, and probably caused by, the termination on it of a primary afferent axon. Bag1 and chain fibres appear later as secondary myotubes in close physical association with the bag2 primary myotube. Temporally the arrival of the motor supply lags slightly behind the afferent supply and is not required for bag2 fibre differentiation.

In the context of this session on clinical implications there are four contributions on single motor unit studies. The first two of them use the technique of cross-correlation analysis between motor unit (MU) discharges recorded during steady voluntary contractions in human forearm muscles.

The job of the scientist is to discover, confirm, and communicate new knowledge. Writing research papers, as discussed in Chapter 8, is a prerequisite to communication, which includes presentations at meetings and publication in books and journals.

Paintings on the walls of caves inhabited by people thousands of years ago (Blakemore, 1988), illuminated manuscripts preserved from the Middle Ages, declarations of love carved on Victorian lace bobbins, the first attempts of four-year-old children to write their names; for thousands of years people have had a strong desire to make their mark, more or less permanently, on paper and other materials.

The purpose of this paper is to summarise the state of Coronavirus epitope research, with an emphasis laid on the most recent achievements, i.e. the correlation between antigenicity and polypeptide primary structure. The antigenic properties of coronaviruses reside mainly in their envelope glycoproteins: the S (spike) protein, a high molecular weight polypeptide which constitutes the petal-shaped peplomers and the M (membrane) protein, a smaller integral membrane polypeptide. Some coronaviruses possess an additional surface glycoprotein, the haemagglutinin-esterase (HE) protein.

The word “evolution” usually evokes thoughts of events which occurred in the distant past, but it is self-evidently an ongoing process. The application of intense selective pressure, for example by the wide-spread use of vaccination, and also the transport of infected animals over large distances may have contributed to what may be considered “short-term” evolution. Papers relevant to putative Coronavirus evolution in both recent and distant time-scales are presented in this volume.

Enveloped viruses carry in their membranes one or more surface glycoproteins. In coronaviruses three such proteins have been identified: a small integral membrane protein (M), a large glycoprotein constituting the characteristic viral spikes (S), and an intermediate-sized glycoprotein (HE). This paper will summarize published knowledge on the properties and function of the small and the intermediate-sized membrane proteins. They will be referred to as M and HE, respectively.

Hydrogels are water-swollen polymer networks. They are of great interest both medically and commerically. Conventional hydrogels change little in swelling with environmental conditions while stimuli-responsive hydrogels may swell or deswell sharply with relatively small changes of temperature or pH. A general review of the principles and applications of these interesting materials is presented here.

Those of us who believe that human welfare is significantly aided by technological progress have a clear motivation to accentuate the positive and to mitigate the negative consequences of technology. We thus share a common objective to allocate our limited societal resources effectively so as to improve public health and safety by minimizing real risks, both present and future.

Virus infections of the central nervous system (CNS) may result in the loss of myelin sheaths without axonal destruction. Severe neurological symptoms occur as a consequence of this phenomenon which is called primary demyelination. The sequence of events leading to primary demyelination during the course of viral infections of the CNS is only partially understood. Although it is well established that cytolytic infection of the Oligodendroglia cell can cause primary demyelination, mononuclear infiltrates in subacute and chronic courses of the disease indicate that immunological events may take part in this process (reviewed by Johnson (1)). For several reasons, investigations into the dynamic interactions between virus infection of the CNS and the local immune response cannot be conducted in man. (1) Usually clinical specimens are restricted to cerebrospinal fluid which gives limited information about pathological events occuring in the brain parenchyma (2). It is not known at which time point of the preceeding systemic infection, the virus enters the brain and biopsies are taken too rarely and infrequently to understand the kinetics of the events (3). The general absence of genetic homogeneity in man complicates attempts to detect the influence of the immunogenetic background on the course of the disease. In contrast, intracerebral infections of rodents with the murine hepatitis virus JHM (MHV-4) are excellent models to study the relationships between virus-induced demyelination and the local immune response. Based on the work of Cheever (2), animal models of JHM virus-induced demyelinating encephalomyelitis have been developed in mice as well as in rats (3–5). In recent years striking similarities in the course of the infection in both rodents have been detected which might give the impression that these two models can substitute for each other. However, subtle but important differences do exist. Therefore, in the present review attempts are made to summarize and compare the knowledge about demyelinating encephalomyelitides in rats and mice, giving emphasis to the role of the local immune response in the brain.

For coronaviruses, the glycoproteins have both historical and biological significance (1,2). Because some coronaviruses were difficult to isolate and propagate, their characteristic large, petal-shaped spikes first allowed coronaviruses to be identified as related agents in a common family. Viral glycoproteins play important roles throughout the life cycle of coronaviruses. Viral glycoproteins interact with receptors on the host cell membrane and are required for penetration of the viral genome into cells by fusion of the viral envelope with the plasma membrane or endosomal membranes. In virus-infected cells, Coronavirus glycoproteins may be glycosylated, acylated, oligomerized, cleaved into subunits by proteases, and transported to specific membrane compartments. The viral glycoproteins participate in assembly of virions, and the intracellular location of viral glycoproteins may determine the location of Coronavirus budding. Viral glycoproteins on the surface of infected cells may permit fusion with adjacent cells, and may make the cell susceptible to immune cytolysis or cell-mediated cytotoxicity, or permit hemadsorption. Epitopes of viral glycoproteins may be recognized by neutralizing, non-neutralizing or hemagglutination-inhibiting antibodies. Thus, elucidation of the structure and functions of Coronavirus glycoproteins is of central importance in understanding the replicative cycle and pathogenesis of coronaviruses.

In 1962 Caspar and Klug conjectured that self-assembly of equivalent or quasi-equivalent protein subunits and viral nucleic acid produces either icosahedral or helical structures according to the biological functions required (1). Some 15 years later Wengler introduced the terms “transcription helices” and “translation helices” to describe the relationship between helical ribonucleoprotein (RNP) structure and genome function for animal viruses containing single-stranded RNA (2). In transcription helices the RNA genome is transcribed into complementary nucleic acid, without permanent disassembly of the RNP. In translation helices the RNA is liberated from the RNP and translated into protein. To account for the fact that no examples of enveloped viruses containing translation helices had been described, Wengler speculated that “the forces exerted on the viral RNP during budding necessitate the design of a helical RNP of such high stability that RNA cannot be released for translation in vivo. Therefore, translation helices will not be present in viruses which obtain a viral membrane by budding”.

In 1984, the appearance of a new porcine Coronavirus related to TGEV was suspected based on an unexpected but widespread prevalence of antibodies to TGEV found in the swine population of several European countries. Most remarkable was the observation that this widespread occurrence of TGEV antibodies was seen in the absence of previous outbreaks or epizootics of diarrhea and also the fact that such findings were made in countries, e.g. Denmark, which had never experienced TGEV infection previously. The ease with which the virus spread, not only within a country, but also across national borders, pointed towards long distance virus transmission, almost certainly by the aerogenic route.

During the last decade recombinant DNA technology has been successfully applied to the development of ‘new’ vaccines. Although there are many examples of successful vaccines which have been developed using the ‘classical approach’ e.g. inactivated, attenuated and subunit vaccines, the demand for a new generation of vaccines is evident. The risk of the escape of a pathogen from a vaccine production facility, the difficulties associated with the production of viral subunits, the high mutation frequency observed in many RNA viruses and the possibility of genetic reassortment and recombination have stimulated researchers to explore new avenues of vaccine biotechnology.

The genomic RNA of coronaviruses has two unique features. Firstly, it is one of the largest stable RNAs known to exist in nature and is unquestionably the largest viral genomic RNA. The complete sequence of avian infectious bronchitis virus (IBV) RNA shows that its size is 27.6 kilobases (kb) (Boursnell et al., 1987). Although the complete sequences of other Coronavirus genomic RNAs are not yet available, preliminary data from several laboratories indicate that the genomic RNA of mouse hepatitis virus (MHV) is as long as 32 kb (Shieh and Lai, unpublished observations). The large size of these RNAs poses a theoretical quandary for the replication of Coronavirus RNA, considering the high error frequency of RNA-dependent RNA synthesis observed in some systems (Holland et al., 1982; Steinhauer and Holland, 1986). How does Coronavirus RNA replicate faithfully despite the high error frequency of RNA synthesis? It is possible that a proof-reading mechanism operates to correct unavoidable mistakes which are expect d to occur in almost every RNA molecule of this size. Secondly, Coronavirus RNA contains a leader sequence (approximately 72 nucleotides) which is repeated at the 5′-end of every subgenomic mRNA species. This structural organization appears to be similar to that of most of eukaryotic mRNAs which contain leader sequences derived by RNA splicing. Yet the Coronavirus RNA genome does not have consensus splicing signals and the virus replicates exclusively in the cytoplasm (Wilhelmson et al., 1981; Brayton et al., 1981), where there is no conventional RNA splicing machinery. Furthermore, UV transcriptional mapping studies suggest that Coronavirus mRNA species are transcribed independently (Jacobs et al., 1981), instead of being derived by cleavage of a precursor RNA. Thus, a new transcriptional mechanism must operate to transcribe Coronavirus mRNAs.

Mass screening for congenital hypothyroidism in newborns has been developed because the irreversible mental retardation caused by this disorder can be prevented by early treatment. These programs include measurement of thyrotropin or total thyroxine (T4), or both, in dried blood samples. Measurement of total T4 is useful for detecting primary, secondary, and tertiary hypothyroidism, but gives false-positive results for subjects with abnormal concentrations of thyroxine-binding globulin (TBG), who do not need to be treated. Hence, we developed an enzyme immunoassay (EIA) and a radioimmunoassay (RIA) for measuring free T4 (FT4) in dried blood samples on filter paper.

Dr. Moskovic compared in his paper 30 patients treated with Amoxapine and Amitryptaline in order to compare their effectiveness in reversing depressive symptoms. Amoxapine had superior results and also showed less side effects for sedation, memory loss, akin-thesia, dry mouth, blurred vision, and light headedness. Suicidal reaction and impaired sleep were the symptoms that improved most rapidly. Hispanic patients were noted to require lower dosages, which is a common denominator of all papers and will be discussed in more detail later. Dr. Moskovic notes that Norepinephrine reuptake is blocked by Amoxapine, but not by Amitriptyline which may explain the differences in rapidity of onset of action.

The sizing treatment of printing papers to make them resistant to penetration by liquids, for example, water or printing inks, also weakens the bond strength between the polymer and the paper in printing processes in which solid polymers create the image on plain, bond-type papers. The adhesion characteristics of a series of business papers treated with either rosin sizes or synthetic, cellulose-reactive sizing agents are described. It is demonstrated that the decrease in bond strength correlates with a decrease in paper wettability, as measured by capillary penetration of organic liquids of suitable surface tension, or as defined by surface energetics using the elution-gas-chromatography technique. Examples are presented, which show that these analytical techniques are effective in specifying paper performance in nonimpact printing technologies (for example, electrophotographic printing and resistive-ribbon, thermal-transfer imaging).

I am pleased to have the opportunity to discuss this fine paper by Dr. Reivich and colleagues. There is a considerable amount of correlative data between clinical and laboratory studies presented by these investigators that agrees quite closely with some of our work in this field. Time permits only specific comments referable to three aspects of this work: (1) cerebral auto-regulation, (2) critical cerebral blood flow, and (3) variations in NADH studies with laboratory preparations.

Dr. Christ has focused our attention on a problem of central importance, not only in the treatment of childhood malignancies, but in the broader field of psychiatry and human behavior. American psychiatry and psychology have tended to neglect the role of the neural substrate in behavior and affect. The case of Milton is a beautiful illustration of the role that insult to the central nervous system (CNS) may play, both directly and indirectly, in influencing psychological function, and of how even well-trained clinicians may ignore it as a result of their theoretical preconceptions.

The discussant fully agrees with G. L. Klerman’s position on operationalized criteria as a necessary condition for investigating the validity of nosological classes. In addition to the strategies proposed by Klerman for determination of validity by internal and external criteria, the potential of two French diagnostic instruments is presented in the following.

Hypoxanthine-guanine phosphoribosyltransferase (HGPRT; E.2.4.2.8.) and adenine phosphoribosyltransferase (APRT; E.2.4.2.7.) function in the metabolic salvage of purines. Complete absence of the activity of HGPRT leads to the Lesch-Nyhan Syndrome, characterised by severe developmental, neurological and behavioural abnormalities and gout.1, 2 Partial deficiencies of the enzyme cause hyperuricaemia and severe gout.3 On the other hand, complete deficiency of the enzyme APRT is associated with urinary stones composed of 2, 8-dihydroxyadenine (2, 8-DHA).4 Although these enzyme deficiencies are extremely rare, an early diagnosis is required to prevent the renal damage.5, 6 Among patients with urolithiasis, an increased incidence of APRT deficiency is proposed.7

All alcoholics drink excessive amounts of alcohol. Surely, those interested in the many aspects of alcoholism, regardless of viewpoint, would agree on this simple but general proposition. Researchers who wish to understand the conditions which lead to excessive alcohol intake are often interested in producing such intake in animals so that hypotheses of alcohol abuse can be evaluated with greater freedom than they can be in humans. Efforts taken over the last decade and a half have shown greater promise in producing excessive alcohol Intake in animals than did the early pioneering efforts. Until recently, for example, it was difficult to arrange conditions so that animals would voluntarily consume enough alcohol to produce intoxication as defined behaviorally or biochemically (e.g., Lester, 1966). It is now possible, however, to induce sustained intoxication in animals using a variety of techniques, and to examine analytically the conditions that induce the effects and the sequalae of this sustained intoxication, such as alcohol tolerance and dependence.

The first investigation of air accident trauma occurred in 1908 at Ft. Myer, Virginia. Orville Wright and Lt. Thomas Selfridge were in an accident in which Orville Wright was killed by falling from the disabled aircraft and suffering a severe skull fracture. In the years between this accident and the beginning of World War II little effort was made by physicians to study air accident trauma. The Luftwagge in Germany, early in World War II, developed the first scientific approach to the pathological and medical investigation of aviation accident trauma.

The study of hemodynamic effects of a pacemaker implantation, as Prof. A. Raineri has shown, is the fundamental problem that characterizes modern cardiac pacing.

The clinical research treatments of childhood cancer present an impressive array of achievements, but an equally impressive array of consequent medical and psychosocial problems. The change in the five or more year survivor rate in acute lymphocitic leukemia (ALL) is indeed impressive: before 1966 only 10–15% of children survived five years, whereas now 95% can expect an initial remission, and as of 1975 60% survived more than five years. Further, most solid tumors have similarly responded: in the 1950s less than 20%, whereas in the 1970s 60–80% survived disease free. Miller emphasized that the refinement of treatment protocols that contributed to this change were only possible through multicenter clinical research trials using random patient assignments.

It was August in New York. More accurately, it was August in Brooklyn, and that is hotter still. Both the heat and the humidity approached one hundred, and Brooklyn does not provide many air-onditioned distractions from such an infernal onslaught.

Light can produce a number of different types of trauma. It can, as the result of photochemical alteration of biochemicals, produce foreign molecules in situ. A number of consequences can result from such photochemical reactions: 1. Protein and lipid and polysaccharide components of membranes can be damaged, thus destroying the integrity of these structures. By reducing the activity of membrane bound enzymes involved in transport, light induced trauma could contribute to alterations in the internal milieu with serious consequences to viability of damaged cells.

Although the etiology of most childhood cancers remains elusive, pediatric oncologists find themselves in the paradoxical situation of having effective therapy at hand for about 50% of all malignancies that afflict children. Thus, we are curing leukemia and osteogenic sarcoma before we have a clue as to the cause. That statement isn’t entirely accurate because we are now aware of a number of associated genetic conditions, immune deficiency states (Kersey et al., 1973), chromosomal abnormalities, congenital malformations (Bolande, 1977), and environmental events that may predispose a child to cancer or significantly increase the risk of developing a malignancy. Foremost on the list of predisposing causes are such diverse disorders as (1) aniridia-Wilms* tumor syndrome; (2) chromosomal instability syndromes (Fanconi1s anemia, Bloom’s syndrome, ataxia-telangiectasia) and leukemia; (3) 21-tri-somy and leukemia; (4) immune deficiency diseases (severe combined immune deficiency disease (SCID), Wiskott-Aldrich syndrome, ataxia-telangiectasia and lymphoma; and (5) multimodality therapy (alkylating agents and radiation therapy) in Hodgkin’s disease or non-Hodgkin’s lymphoma followed by a second malignant neoplasm, acute non-lymphocytic leukemia.

Previously, there have been few publications on free amino acid analysis in human tears. These studies used dated techniques based on paper chromatography. Because of their poor determination and the need of a high volume sample for analysis, all of the assays were done on reflex tear and produced, at best, only semi-quantitative results. To date, the role of tear free amino acids in the economy of the cornea and conjunctiva has not been studied, and no specific diseases have been reported in which qualitative or quantitative derangement of the tear amino acid composition is implicated.

The benefits of hormone replacement therapy (HRT) are numerous: It provides relief of menopausal symptoms, reduces the risk of osteoporosis and accompanying fractures and may potentially aid in the prevention of various other illnesses, including Alzheimer’s disease and cardiovascular disease (CVD) [1 – 4]. Despite the established and potential benefits of HRT, which have been shown to outweigh its possible risks, fewer than one-half of eligible women in the United States are currently using it [1,5. Furthermore, only a fraction of current users will continue therapy for more than 2 years [6]. Part of the reason for this problem with discontinuation is the lack of consistency in the literature regarding risks and benefits. For example, the American Heart Association recently suggested in a position paper that there is no benefit to taking estrogen for secondary prevention of CVD and questioned whether there is any benefit to it in primary prevention [7].

The purpose of this short paper is to give a briefly review of the existing epidemiological literature relevant to human health on the association between exposure to electromagnetic fields in the radio frequency area and risk of cancer and while doing so address some of the methodological problems in these studies.

We have developed a non-clotting based heparin assay. It is established by the attachment of protamine (a heparin antidote) to a porous filter paper strip; and the subsequent migration of heparin sample through the filter paper in an ascending or descending manner. The area of paper to which heparin adsorbed will be proportional to the heparin level in the sample. This region is visualized by spraying methylene blue NNX (a dye that interacts with heparin and the interaction causes a metachromatic shift of the dye’s absorption maximum from blue to purple) solution onto the paper strip upon the exhaustion of the sample reservoir. This approach has proven to be capable of detecting and differentiating plasma heparin level within clinical range in a relatively time efficient and accurate manner.